As final preparations were made for the start of the Large Hadron Collider's (LHC) Run 2, the ATLAS Control Room was the centre of activity. Here are images from the three days that were landmark events -- first collisions at 900 GeV on 5 May, first test collisions at 13 TeV on 20 May , and 3 June that marked the beginning of physics data-taking at 13 TeV and ATLAS' journey into unexplored frontiers of physics.